Step 1: Cook the Pasta and Prepare Chicken
Preheat your oven to 375°F (190°C) if baking. Bring a large pot of generously salted water to a rolling boil. Cook the pasta according to package directions until al dente. Drain and set aside. While the pasta cooks, toss the shredded chicken with the ½ cup of Buffalo sauce in a bowl until evenly coated.

Step 2: Create the Roux (The Sauce Foundation)
In a large Dutch oven or heavy-bottomed pot, melt 4 tablespoons of butter over medium heat. Once melted and bubbling, sprinkle in the ¼ cup of flour. Whisk constantly and cook for 1-2 minutes until the mixture (roux) is blonde and fragrant, but not browned.

Step 3: Build the Creamy Base
Gradually pour in the warmed milk while whisking vigorously to prevent lumps. Continue to cook, whisking frequently, until the mixture thickens enough to coat the back of a spoon, about 5-7 minutes. Reduce heat to low.

Step 4: Create the Ultra-Cheese Sauce
Add the cubed cream cheese to the warm milk base. Whisk until completely melted and smooth. Begin adding the shredded cheeses (cheddar, Monterey Jack, and Parmesan) one handful at a time, whisking until each addition is fully melted and incorporated before adding the next. This patience ensures a smooth, non-grainy sauce. Stir in the garlic powder, onion powder, smoked paprika, and dry mustard.

Step 5: Buffalo-ify the Sauce
Pour the remaining Buffalo sauce (you can start with ¼ cup and adjust) into the cheese sauce. Stir to combine. Taste and adjust for heat and seasoning. The sauce should be boldly flavored, as it will mellow slightly when mixed with the pasta.

Step 6: Combine Pasta, Chicken, and Sauce
Add the drained pasta and the Buffalo-coated chicken to the pot with the cheese sauce. Gently fold everything together until every piece of pasta and chicken is luxuriously coated.

Choose Your Adventure:
A) Stovetop Creamy Version: Heat through for 2-3 minutes, then serve immediately garnished with chives, a drizzle of dressing, and extra Buffalo sauce on the side.
B) Golden Baked Casserole Version: Transfer the mixture to a greased 9×13 inch baking dish.

Step 7: (For Baked Version) Create the Crispy Topping
In a small bowl, combine the Panko breadcrumbs, ¼ cup Parmesan, and 2 tablespoons of melted butter. Mix until the crumbs are evenly moistened. Sprinkle this mixture evenly over the top of the mac and cheese.

Step 8: Bake to Bubbly Perfection
Place the baking dish in the preheated oven. Bake, uncovered, for 20-25 minutes, or until the topping is golden brown and the sauce is bubbling vigorously around the edges.

Step 9: Garnish and Serve
Remove from the oven and let it rest for 5 minutes. This allows the sauce to set slightly. Drizzle generously with blue cheese or ranch dressing, and sprinkle with fresh chives and sliced green onions. Serve hot, encouraging everyone to get a bit of the crispy topping and cool dressing in each bite